MON-LB106 The Effect of the Ketogenic Diet on Aldosterone Over 6 Weeks

Introduction: A ketogenic diet improves type 2 diabetes, metabolic syndrome, and cardiovascular disease. Weight loss studies using caloric reduction have demonstrated a decrease in aldosterone, but there is limited data on the effect of a ketogenic diet on aldosterone. Thus, we evaluated the impact of a ketogenic diet on aldosterone in overweight or obese individuals over 6 weeks. Methods: This 3-arm prospective controlled feeding study evaluated aldosterone and renin concentrations over 6 weeks on a hypocaloric (25% energy restricted) ketogenic diet + placebo (KD+PL), ketogenic diet + ketone salt supplement (KD+KS), and a low-fat diet (LFD). Sodium intake consisted of 6100 mg, 2300 mg, and 2000 mg for the KD+KS, KD+PL, and LFD groups, respectively. Both ketogenic diets provided 40 grams(g) day of carbohydrates, 1.5 g/kg reference weight of protein and remaining calories provided as fat. The LFD provided 25% total fat, 1.5 g/kg reference weight of protein, and 100g of carbohydrates. Serum aldosterone was drawn fasting in upright position at 0, 2, 4, and 6 weeks. Scatter plots were used to explore the residual and predicted associations between aldosterone with other measures after accounting for time and group effect.Results: Twenty-four participants in the ketogenic diet groups were matched for age and body mass index, then randomized to either the KD+PL or KD+KS group. A separate group of 12 matched participants were specifically recruited for the LFD group. The median age was 33 years. Weight decreased 6, 8, and 7 kg on average in the KD+KS, KD+PL, and LFD groups, respectively, over 6 weeks (p<0.05 for all). Systolic blood pressure (SBP) improved from 117 and 115 mmHg in the KD+KS and KD+PL groups to 110 mmHg over 6 weeks while the baseline mean SBP 118 in the LF group did not change. Baseline mean aldosterone of 13.6 and 13.6 ng/dL in the KD+KS and KD+PL groups increased to 33.3 and 27.3 ng/dL over 6 weeks (p<0.001). Baseline mean aldosterone of 8 ng/dL in the LF group non-significantly changed to 11.5 ng/dL over 6 weeks (p>0.05). Using predicted value associations, increases in ketones were positively associated with higher aldosterone (R2=0.86; p<0.001). Conclusion: Participants on a ketogenic diet had significantly elevated aldosterone levels throughout the study while participants on low fat diet had little change. Unexpectedly, aldosterone was significantly higher in the high sodium vs. low sodium ketogenic diet. There was a significant association between ketones and aldosterone suggesting that ketones may play a stimulatory role on aldosterone synthesis or secretion.